In this condition, the pupil is not centered in the iris. When the pupil is off just a bit, the dogs seem to cope well, but can have trouble when the condition is more pronounced. Microphthalmia, or an abnormally small eye, is the most common eye defect seen in homozygous merles. This can vary from just noticeable to appearing to have no eye at all (anophthalmia).
Children begin to develop hand dominance around 2-3 years and this should be well developed by age 5 and fully developed by age 6. Use of a dominant hand before 2-3 years time may occur because of abnormal fine motor development. It could also be the result of intracranial injury or injury to a limb with appropriate compensation by the other limb.
Preference for the right or left hand is, in part, genetic. Prior studies have shown that some of these one-sided tendencies emerge early. Fetuses suck their right thumb more often than their left; newborns on their back turn to the right more frequently. Most children grow up to be right-handedâin part because of these innate, early leanings, scientists believe. But the timing of when one hand emerges as the dominant one for most tasks remained unclear.